Apparatus for use in packaging of product



Feb. 16, 1960 A. H. BURNETT APPARATUS FOR USE IN PACKAGING OF PRODUCT Original Filed Jan. 9, 1957 3 Sheets-Sheet 1 llllllll "'l' llllllllllllll.

'F-----.'-- OI INVENTOR. Al ELY/11705 ll- BURNETT BY E ATTORNEY Feb. 16, 1960' A. H. BURNETT 2,924,922

APPARATUS FOR USE IN PACKAGING OF PRODUCT 9 Original Filed Jan. 9, 1957 3 Sheets-Sheet 2 INVENTOR. 1 ALEXANDER h. BURNETT 8y may/15;,

A 7' TOR/YE 7 1960 A. H. BURNETT 2,924,922

APPARATUS FOR USE IN PACKAGING OF PRODUCT Original Filed Jan. 9, 1957 I s Sheets-Sheet a I .95 5:94 25 I26 i 154 INVENTOR. AL EXA IVDER ll. BURNETT svfl iy/a ATTORNEY e No. 699,434

APPARATUS FOR USE IN PACKAGING OF PRODUCT' a n Q Alexander 1H. Burnett,- Chicago, Ill., assignor to Swift s: 'Company Chicago, 111., a corporation of Illinois Continuation of application Serial No. 633,338, January 9 1957. This application November- 26, 1957,. Serial 10 claims. (ci. 53495):

This invention relates in general to theva'cuum packaging of objects in fiexiblewrappers and more partlcularly to an apparatus adapted 'to vacuum'ize and seal a plurality of product containing packages in ajjcon'tinuous-operation. This application is a continuation'ofapplication Serial No. 633,338, filed January 9, 1957,now

abandoned. 'An important development in packaging technology U fstw Patei Q 9 RetentedgFehlG, 1960* y 11in which is meat mama-shallow shaft i2. oils in recent yearsis the widespread use of flexible wrapping materials inthe formation of hermetically sealed'pack- I ages; The product to be packaged is placed in a tube of flexible wrapping material or b etween two sheetsjqf said materiaL: air is exhausted from the area surrounding the to provide an air-tight package. 'Machin'espresently used for packaging products inthis manner are unsatisfactory for a number of'reasons'. Large scale product on requires that packages be continuously vacuumized and sealed in rapid successionfwith a minimum of operator attention. straight-line machines are operated at speeds necessary for economical productionhowever, the resultant pack ages are unsatisfactory because of lnsufiicient vacuumization or improper sealing or a combination of the two. If, on the other hand, these straight line machines are operated so as to allow thelpackage' to remain 'in the1vac-, uum chamber for a time" sufiicient to insure' complete air exhaustion, the time'iuterval between packages being vacuumized and sealed is too great for profitable operation.

It is therefore an objectof this invention to provide a a device adapted to the rapid and continuous productionof hermetically sealed packages which retain desirable j air-tight characteristics over a substantial period of time."

Afurther disadvantage of prior art vacuum packaging machines is the greafamount of operator attention necessary for efiicient operation. An operator must be on duty constantly to introduce unsealed packages to the It has been found that if prior, art

product, and the edges of the flexible material are sealed end of, shaft 12 is closed while the other end communicates with a vacuum pump 13. Approximately midway: between bosses 11,- shaft 12 has radial openings 14 throughthe wall thereof. 1

Fitting about shaft 12. is a sleeve 16 forming a part of a supporting headgenerally 17-which in the illustrated embodiment carries -fo'urj vacuum chambers. The vacto operating arm 28. a

' Ateach side of the vacuum chamber is a sealing means comprising a backing bar 29 and a movable heated sealing-bar 30. Th eheated sealing bar is movable in a vertical direction through upper wall 19, of the chamber and normally is held in the raised position by springs 31 connected between pins 32and the upper wall 19 of the chamber. The upper end of the sealing bar 30 forms an extending actuating member 33. The actuating members 33 of the sealin g bars at eachfside of the chamber are at opposite sides of the center line of the sealing bars. For example, note that the actuating member 33 in Figs.

1arid, 2 isat therear. side of the center line while the actuating member 33 of the sealing .bar at the opposite end ,of they chamber is forward of the center line in Fig. l. The heating of the sealing bars 30 is' accomplished by meansof a resistance coil 35 connected by; meansof wires,37 and 38 to contacts39 and 40, respe'ctively, which arefinoun'ted on sleeve 16 but insulated therefrom. Contact 4 0 r id es on a slip ring 41 whilecontact 39 rides 0111a; slip ring 42. The slip rings are mountedon pipe 12 but in'sulat'ed therefrom. Electric power is;

fed to the sliprings from. a suitable source of electricity, not shown} A,

In theupper wan; 1 9. jdfgthe vacuum chamber is a pres- I sure plate 45 to which i's'attaehed' a pin.46 having a head machine and to remove the sealed package afterthe vacuumizing and sealing operation.

It is therefore another object of this invention to provide a vacuumizing and sealing apparatus capable of substantially completely automatic operation.

Additional objects, if not specifically set forth herein, V

will be readily apparent to one skilled in the art from the following detailed description taken in" conjunction with the drawings, in which:

Fig. l is an end view of an embodiment of the invention withthe feeding mechanism removed. The view is taken along the line 11-of Fig. 2.

Fig. 2 is a side view taken along line 2-2 of Fig. 1 Fig. 3 is an enlarged partialsegment of the top wall of the cavities illustrating the structure of the pressure plate used therein. Fig. 4 is a partial section Fig. 5 is an end view taken at line 55 of Fig. 2. The illustrated embodiment is constructed on a frame generally 10. Attached to frame 10am 8. pair of bosses taken at line 44 of Fig. 2.

47 thereon. A sleeve'48Qis journaled in a boss 49forminga part of the top -wall :19 of the. chamber. Within' sleeve 48 is an opening50,,theupper end of which is. of a size to r eceivehead 47'of'pin 46 while thelower end of theop'ening substantially smaller in diameter than head 47 and of a size to only fit about the body of. 1

pin 46. A spring 51 is. fitted within the upperendpf opening 50fbetweenthe top wall thereof (which, of course,-is removable. topermit the structure to be assembled anddisassembled) and'th'e'topof head 47. R0.- tatablyymounte'd on the tgpof sleeve.48 'is a cam follower 52.. Sleeve'48 is held in the raised position by a spring 53 positioned between the top of wall 19 and a shoulder a 54 at the top of sleeve .48-justbelow cam follower 52.

A passageway 57 passes through supporting member;17

with oneend being in. communicatiomwith the vacuum 1 chamber and theother end being in'communication with an opening 58 through'sleeve 16.. In theposition'in' which the top vacuum chamber of Figs. 1 and 2appears, there is no communication" between opening 58 and opening14' in pipe 12; Howeven-these openings are in the same plane so that as the supporting member 17 rof tates as hereinafterdescribed; opening 58 will come intu t communication with opening 14 so'as to apply a vacuum to the vacuum chamberthrough'. passageway 57. Passageways 59 are formed in the base 18 of the chamber in communication with passageway 57 so as to prevent the packages in the chamber. from obstructing the vacuum drawn through passageway-57;

Supporting head 17 is driven a step at a timeby a conventional Geneva drive which is connected so that.

ne. of the vacuumi'ehamberswill' be' h'eld in the upper positionillustrated by the position of the vacuum charm ber just.describ'edfduring each dwell period of the Geneva 1 drive. .:This drive consists of a' dr'iveri memb'er'60 at:- tached to sleeve 16. Driven rnerr iber 60 has a slot 61- for, eachof the vacuum-ehamberswith arcuate segments 62 lntermedlate eachof slots-61'. ,k-Driving memberit iszattached to a shaft fiftfl'suitably' journal'ed in bearing 65. Driving member 63 comprises; a wheel 67 andan' arm 68. Wheel 67 has a cutout" 69. Arm 68 has. a roller 70 projecting therefrom and adapted to enter slots 61 of driven member 60. As is readily apparent,

. rollers70 upon entering a slot 61 rotate driven member 60w'through 90, the rotation being permittedhby the cutout 69 in'wheel 67. [After rotating through 90? the circular periphery of wheel 67 enters 'arcuate' segments driven by a chain 110 fromv a sprocket 111 on shaft 64.

62 to hold the driven member in that position until roller 70: rotates through the-remainder, of a re volution' to enter the next slot '61 in driven member 60. Shaft' 64 is rotated by means of'a chain 71 passing about a sprocket 72 attachedto shaft 64 and also rotating'about a-sprocket on the output shaft of asuitable source of power, such as a slow speedelectric motor, not shown. '.About the. outside of-supporting member 17 and the vacuum chambers is acylindrical casing 75 forming a part of frame 10. Ca'sing75 is employed as a mounting for the various camsoperating the portions of the vacuum chambers. A cam 76 'cooperates'vvith cam follower 52 to move the pressure plate'45 against the packages in the vacuum chamber. Cam/7,6 is continuous and extends the same distance out except for a recessed portion 77 at'the top of the machine. Thus when a" vacuum cham- 5 boss forming apart arm 102 is'atta'ched to the opposite end of shaft and of frame 10. An actuating carries a cam follower 103 at the end thereof. A cylindrical positive action cam 104 has a cam slot 105 in which is received cam follower 103. Cam 104 is secured to a shaft 106 suitably 'journa'led inbearings 107 and 108. A sprocket 109 is attached to shaft 106 and is At the left end of the machine in Fig. 2, the entering end forfthe packages,is. arsuppoi'ting plate forming apart of frame 10. Adownward reversebend at each sideof the plate, 115 forms away 116 for slide 117.

Attthe bottom of onejend of-slide 117 is a'post 118 secured to 'the'slide to: engage one end of aspring 119. The opposite end of spring 119 is hooked on across bar 120 held-by projecting meinbe'rs 1211." A cross brace 122 is used to strengthen the reversebent portions forming ways.,116; but positioned. far enough. forward so as tofallow freeflmovemeilf 0f',po'st118between the rear- I ward segments offlthe reverse. bent portions.

Attached tQ-de'pendlng ember 91 is. across bar 125 having. two. arms 126.. p'roj'ectjing downwardly therefrom.

,At -the"lowerfendlof arms'126'are deten'ts 1 27 pivotally mounted on pinsf128Q The forward end of each detent 127 .is hooked .to engage stops129secured to slide 117.

Stops 129projeetfthrough slotsin supporting. plate 115. The rearward side of stops 129m sloped to form a cam surface..130 to permit the'detents 127 to ride thereover.

Alongthe outside ofdet'ents127' are cam surfaces 131 which1cooperatewithfiXedIcamslIQZ' fixed to the sides of supportingfplate 115. A'l springl133is hooked between ost 134.onftheflside'of.eachlof arn'i's. 126 and the top ber is positioned atthe-top of the"machinethe'jpressure plate 45 is retracted (the'position'shownf in Fig- 3) by cam follower 52being extended under the urging" of spring '53. As thevac'uum chambers leave thetopmostposition and move through the other three'positions, cam- 76. is contacted by cam followerj52fto push the pressure plate 45 down against the packages inthe chamber. r

A pair of cams 80 and'81 arefpositioned'at the top of casing 75 to open doors 22 and .23. Cam followers 82'and 83, respectively, contactcarns181 and 80; respectively; to swing the doors openja's, eachvacu'um chamber approaches its uppermost position. "As that" vacuum chamber leaves the uppermost position, earns 80 and 81' cause the doors to close withthe doors'subsequently being held closed by the application of vacuum to the chambers. The force of gravity'acting on doors 22' and 23 assists in, the initial closing of the doors.

Atthe right side oficasing 75 in Fig. 1 are apair of earns 85' and 86 to operate the heated..sealing' bars, 30. Actuating'member' 33 contacts cam 85' and at thesame time actuating member 33' contacts cam 86. .In each case the cam pushes the actuating member inwardly to move theheated'sealingj bars 30 against the ends ofth e ofeach detent" 1'21. Stops '135lirnit the clockwise rotation'of detents1f121 (as viewed in. Fig.2).

The structure: for removing the packages from the vacuum chamberis attached to the opposite end of slide 90.1 A downwardly projecting memsamo is secured to slide .90. andcarries' a horizontal arm 141. A finger 142 is pivotally attached to arm. 141 by means of a pin 143.

- ber,

package in the chamber and topress those endsfb'etween the heated sealing'bar 30and the backing bar' '29;

The structure for moving the'packages into. the chambers is best illustrated in-Figs. 2. and 4 A power slide 90 is journaled in casing 75 for longitudinal'movement insaid casing. Attached-toslide' 90is a depending member 91.

by a pin-94. The two tines. 9.3 extendgbeyond pin 94 to, contact a stop 95 which limits the-clockwise rotation of pusher 92 as seen inFig. 2.. i I.

At one end of slide. 90 is 'secureda headed pin 97 which is received in a slot" 98 in the end of an arm 99 (Big; 1). Arm 99 is, attached to. a. shaft. 100'journaled A pusher92 has the upper end cut'to a fork configuration. (see-,Fig. 4),.withtthetwo tines 93 of the fork being pivotallyattached to depending member 91;.

A pusher. plate. 144is attached to the end of finger 142.

A" slide 4145 is mounted in. vvays 146 forming. a part c of brackets 147 secured to "frame 10. Secured to slide I atone side thereof are a pair of stops 148 and 149.

Between stops 148 and'149 is an L-shaped actuating member 150 Isecured to downwardly projecting memper-ate the described embodiment the vacuum pump 13 is started audasuitable electrical connection is madeto the sliprings 41: and 42. to feed resistance coils 35. Partially formed packages of product are positioned on supporting. plate- 115. in approximately the positionshown in Fig. This. may. be done by hand or by delivery to thatpoint by other, apparatus; One substantialv advantage of myinvention isv that the-initial positioning of thesepackagesis not critical and the feeding mechanism (notshown) for doingso neednot be closely calibrated in that respect.-

Preferably these packages havebeen partially formed 1 60 I with the ends sealed ,exceptfor a gap 156 in. the central portion of the seah l prefer to have the ends thus partially sealed because the film is thereby held in place,

rotateand tomove'cam. follower 103 to the left in Fig.-

2. This draws slide 90 to the left. As detents 127 come into contact with-carns.-132,-the-cams rotate: the detents counterclockwise. (Fig. 2') so asito disengage-the detents from ..stops-1219.- Uponthat; disengagement spr-ing1-19 moves. slide11-7 against'-. the. face-of supporting head 17 cause it to enter into the vacuum chamber.

to form a bridge for the package 155 to enter the uppermost vacuum chamber. With the continued movement of slide 90, pusher 92 contacts the forward end of the package with the pusher thereby pivoting the pushercounterclockwise to pass across the top of package 155. The pusher finally arrives at the dotted line position illustrated at 92 in Fig. 2, with the pusher having fallen behind the package as it passed'completely beyond the rear side of the package.

With the foregoing described movement of slide 90, depending member 140 also moved to the left. In doing so actuating member 156 contacted stop 148 to move,

Upon passing beyond in Fig. 2. As it moves to the right, pusher 92 pushesv package 155 across the bridge formed .by slide 117 to At the same time pusher 144 ejects the package previously in the vacuum chamber from that chamber across the bridge formed by slide "145.. As slide 90 approaches the end of its stroke actuating member 150 contacts, stop 149 to withdraw slide 145 from the side of supporting head 17. During the samev movement of slide 90 detent 127 contacts the cam surface 130 of stop 129 to pivot the detent counterclockwise,;and permit the detent to pass forwardly of and in a position to engage stop 129. Cam 104 then causes slide 90'to commence moving to the left in Fig. 2, at which timedetent'127 engages stop 129 to draw slide 117 away from the side'of supporting head 17. Cam 104 then'enters a brief dwell period.

During the dwell period of cam 104 the Geneva drive rotates sleeve 16 and supporting head 17 counterclockwise 90 in Fig. 1. As the top vacuum chamber with the new package moves away from the uppermost position of Fig. 1, earns 80 and 81 close doors 22 and 23 to the vacuum chamber. At the same time cam follower 52 is forced downwardly by contact with cam 76 to move the pressure plate 45 against the top of the package. The amount of pressure that will be applied between pressure plate 45 and the bottom 18 of the vacuumchamber is determined by the strength of spring 51. This is achieved by causing cam 76 to move cam follower 52 'a distance greater than the distance necessary for the pressure plate 45 to reach the sideof, the package. The excess travel of cam follower 52 is taken up by the compression of spring 51. As the vacuum chamber approaches the left side position in Fig.1, opening 58 in sleeve 16 comes into communication with opening 14 in pipe 12. The vacuum pump 13 thereby is caused to evacuate the vacuum chamber through pipe 12, openings 14 and 58, and passageway 57. t a

The package in the vacuum chamber remains under mechanical compression and under a vacuum, during the period of time that it is in the left-hand positionin Fig. 1, the lower position, and the right-hand position. Of course, duringthis period packages are being removed from, and new packages inserted into, each of the other vacuum chambers'as they traverse the top position. As the vacuum chamber leaves the right-hand position in Fig. 1 and approaches the upper position, actuating member'33 contacts cam 85 and actuating member 33 contacts cam 86. During the period of time that these actuating members are traversing their respective cams, the

cams push the actuating members down so as to bring the heated sealing bars against the top of the unsealed portion of the ends of the package and to press those portions against backing bar 29. The length of time that this occurs can be varied by varying the length of 6 the cams SSand 86. During this time the heated sealing bars cause the unsealed portions of the thermoplastic"? film to cohere and form a fluid-tight seal.

As the vacuum chamber continues to move toward the top] position the heated sealingbars are released and raised by springs 31. Cam follower 52 enters the recessed portion 77 of cam 76 so as to permit the pressure 1 plate 45 to be raised by the action of spring 53. Also during the same .period of movement, opening 58 in sleeve 16 passed the end of opening 14 in pipe 12, thereby cutting off the vacuum to] the vacuum chambers. The

cams 8t? and 81 move arms 28 and 27, respectively,-'so as to open doors 22 and 23, respectively. a

It will be noted that my invention provides a straight line movement into and out of the vacuum chamber." This is important in. obtaining rapid operation and also facilitates the proper positioning of the packages in the vacuum chamber. The packages are held .in this proper position by pressure plate 45 which at the same time applies mechanical pressure to the exterior of .the package to facilitate in removing the air therefrom. Com pared to conventional straight line machines the period] of vacuumization is about doubled while at-the same time nearly doubling the number of vacuum sealed packages produced per minute. a

The foregoing description of a specific embodiment is for the purpose ofcomplying with 35U.S.C. 112. and should not be construed as imposing unnecessary limitations on the appended claims inasmuch as modifications thereof will be readilyapparent to those skilled in the art. Examples of such modifications would be avariation in the number of vacuum chambers. One feature of the present invention is the ability to apply a vacuum to-an individual package for some time before the actual seal is made, yet the limiting feature on which the speed of operation is determined is the rapidity with which the packages can be inserted into and removed fromthe open vacuum chamber If the period of time required for that insertion and removal multiplied by one less than the number of chambers is greater or less than what is needed to achieve adequate evacuation of the packages in the closed chambers before the packages are sealed,- the number ofchambers may be varied accordingly. In some embodiments it might be desired to use pressure sensitive adhesives to seal the ends 'of the film rather than thermoplastic films. In such case the heating elements 35 could be eliminatedor just'not energized, with the movable sealing bar 30 performing the function of producing'a seal merely by applying pressure'to the un-' sealed portion of the ends of the film. The size of these components could similarlybe varied to accommodate different sized elements or difierent sized unsealed portions in the ends'of the partially formed packages.

I claim: 7 l v 1. A device for use in sealing an extending end of a plurality of partially formed packages under controlled atmospheric conditions, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said head having a plurality of chambers, each having a package supporting base and three walls about said base with the two ends thereof being open, said base being substantially tangential to a circle of revolution aboutsaid axis,- power means connected to said head to rotate said head a step at a time from a position at which each chamber, when each chamber is at said position, has the base thereof generally horizontal, means to close said two ends of said chambers except when said chambers are at said position, means to insert a partially formed package in each chamber when each chamber is at said position and to remove the finished package from that chamber, means to adjust the atmoseach chamber after the atmosphere in each chamber has position; v a r L 2. A device for use-in? sealing an extending: end of a been adjusted: and beforerthe chamber returnsto said" plurality of partially formed packages under controlled atmospheric conditions, .said dEVlCfllIlCllldlllg a frame, a

supportinghead mounted on said framefonrotation about a generally horizontal axis, said headhavmga plurality of chambers,-each having apackage supporting base and three Walls about said base with the two ends thereofi being op'en,,said base beingsubstantially tangential to a base thereof-generally horizontal, means to close said two ends'of said chamberssexcept when said chambers are circle of'revolution about said axis, power means: connected to said head-to-rotatesaid head a step at a time position, a pressure plate in eachchamber normally positi'oned adjacent-the Wall oppositesaid base, means operatively connected to said plates to move each plate towards itsresp'ective base after the respective chamberleaves-said position so as to apply pressure to thepackage between said. plate and said base and to return said plate to said normal positionbeforethe respective chamber returns to said position and said package is removed, and means to seals'aid ends of the packages in each chamber'after the atmosphere in each chamber has been adjusted and before the chamber returns to said position.

- 3. A device for use'in sealing an extending end of a plurality of partially formed packages under controlled atmospheric conditions, said device including a frame, a

supporting head mounted onsaid frame for rotation about", a generally horizontal axis, said'head'havin'g a-plurality" of chambers, each having a package supporting base-and three walls about said base with the twoends thereof being' open,'said base being substantially tangential to a circle of revolution about said axis power means connected to said head to rotate said head a step at a time from a position at which each chamber, when each chamberris at said position, has the base thereof generally horizontal, means-to close saidtwo ends of said chambers-except when said chambers are at-said position, means to inserta partially-formed package in each chamber when each chamber is at said position and to remove the finished package from thatchambeii means to adjust 1theatmosphere in saidchambers after said chambers leave-[said position, and means to seals-aid ends of th'erpack ages in each chamber after the atmosphere in each chamber has" been adjustedand before the chamber returns tosaid position, said last mentioned means comprising apacking bar member and a heated sealing member, one of' said members beingpositionedat' a' fixed elevation with-respect to said base, and actuating means operatively connected to the other of said members to move said other member toward and awayfrom said one member.

4. A device for use in sealing an extending end of a plurality of partially formed packages under controlled atmospheric conditions, said device including a stationary hollow shaft mounted with the longitudinal axis thereof substantially horizontal; a supporting head mounted for rotation about said axis, said head having a plurality of chambers, and a sleeve about said shaft, said sleevehaving a plurality of radial openings therein with one'openingfor each of said chambers and'in communication with" the respective chamber, each of said chambers havin In package supporting base and three walls aboutrsaid base:

at said position meansto insert a'pa'rtially formed packagerin each chamber whenxeachichamber is at said position and'fto remove the finished package: from that chamber, said shafthaving an opening therein positioned inthe'same'plane as; said radial openings in said sleeve, said shaft opening being positioned to ,be in alignment with the radial opening for each chamber only'after said j. chamber leaves said position and before it returns to said p.osition,- andmeans communicating with the hollow interior of said shaft torcontrol-the atmospheric conditions thereinandinthe chambers incommunication therewith.

5. A device for use in sealing an extendingend of a plurality of partially formed packages under controlled atmospheric conditions, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said=head'having a plurality 'of chambers, each having.a'package supporting base and three walls about said base with thetwo ends thereof being open, said base beingisubstantially tangential to a circle I ofrevolution about said axis, power meansconnected to means to close said twoends of said chambers except with the two ends thereof being open, said. base being; substantially tangential to a circle of. revolution abo'ut saidaxis, power means connected to said-head torotate said heada step at a time from a'position at which-each chambe y when each chamber is-at said -position,-lias the said head to rotate said heada step at a time from a position at which each member, when-each chamber is at said position, has'the, base thereof generally horizontal,

when said chambers are at said position, saidlast mentioned means comprising'a door-foreach end of each of said chambers, said door movable between an open position and a closed position,-means urging said doors towardone of. said positions, a c'am'about at least a side of said axis, cam followers operativelyconnected to said doors and positioned, to contact v -said 0am to move said doors to said'other position, means-to insert a partially formed package in each chamber when each chamber is atsai'daposition through one end of said chamber and to remove thefinished package from that chamber through the opposite end of said chamber, means to adjust the atmospherein saidchambers .after said chambers leave said position, and means to'seal said ends of the packages plura'lity of' chambers, each having-a package supporting base and three walls about said base with the two ends thereof being open, said base being substantially tangential to a circle of revolution about said axis, power means connected to said head: to rotate said head a-step at a time from a positionat'which each chamber, when each chamber is at said position, has the base thereof generally horizontal, means to close said two ends of said chambers except when said chambers are at said position, said last mentioned means comprising, a door for each end of each'ofsaid chambers and movable between an open position and' a closed position, means urging said doors toward one of said positions, a cam about at least a side of said axis, cam followers operatively connected to said doors and positioned tocontact said camtto move said doors to said other position, means to: insert-a'partially formed package in each chamber when each chamber is at said position through one end of said chamber and to removethe finished package from that chamber through the opposite end ofsaid chamber, means toyadjust the "atmosphere in said chambers after said chambers leave said'position, a pressure plate in each chamber movable toward and away from said base, re-' a respect tosaid base, a second cam about said axis, a

cam follower operatively connected to said plate and contacting'said second cam,'said urging means and said cam being constructed and arranged to apply pressure to the package in each said chamber after each said chamber leaves said position and to withdraw said pressure before each said chamber returns to said position, and means to seal said ends of the packages in each chamber after the atmosphere in each chamber has been adjusted and before the chamber returns to said position.

7. A device for use in sealing an extending end of a plurality of partially formed packages under controlled atmospheric conditions, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said head having a plurality of chambers, each having a package supporting base and three walls about said base with the two ends thereof being open, said base being substantially tangential to a circle of revolution about said axis, power means connected to said head to rotate said head a step at a time from a position at which each chamber, when each chamber is at said position, has the base thereof generally horizontal, means to close said two ends of said chambers except when said chambers are at said position, means to insert a partially formed package in each chamber when each chamber is at said position and to remove the finished package from that chamber, said last mentioned means including a pusher movable toward and away from the chamber at said position to insert a package into the chamber, and a finger movable into and out of said chamber, said finger being pivotally mounted whereby it will pass over the package to fall behind the rearward end thereof to withdraw the package as the finger moves out of the chamber, means to adjust the atmosphere in said chambers after said chambers leave said position, and means to seal said ends of the packages in each chamber after the atmosphere in each chamber has been adjusted and before the chamber returns to said position.

8. A device for use in sealing partially formed packages under controlled atmospheric conditions, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said head having a plurality of chambers, each having a package supporting base and two opposing open ends adjacent said base, said base being substantially tangential to a circle of revolution about said axis, power means connected to rotate said head, means to close said two ends of saidchambers during a major portion of the rotation of said head, said last mentioned means comprising a door for each end of each of said chambers, said doors being movable between an open position and a closed position, means urging said doors toward one of said positions, a cam about at least a side of said axis, cam followers operatively connected to said doors and positioned to contact said cam to move said doors to said other position, means to adjust the atmosphere in said chambers after said ends are closed, and means to seal said packages in said chambers after the atmosphere in said chambers has been adjusted and while the ends of said chambers remain closed.

9. A device for use in subjecting packages to a controlled atmosphere, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said head having a plurality of chambers, each having a package supporting base and two opposing open ends adjacent said base, said base being substantially tangential to a circle of revolution about said axis, power means connected to rotate said head, means to close said two ends of said chambers during a major portion of the rotation of said head, said last mentioned means comprising a door for each end of each of said chambers, said doors being movable between an open position and a closed position, means urging said doors toward one of said positions, a cam about at least a side of said axis, cam followers operatively connected to said doors and positioned to contact said cam to move said doors to said other position, and means to control the atmosphere in said chambers while said ends are closed.

10. A device for use in sealing packages, said device including a frame, a supporting head mounted on said frame for rotation about a generally horizontal axis, said head having a plurality of chambers, each having a package supporting base and two opposing open ends adjacent said base, said base being substantially tangential to a circle of revolution about said axis, poser means connected to rotate said head, means to close said two ends of said chambers during a major portion of the rotation of said head, said last mentioned means comprising a door for each end of each of said chambers, said doors being movable between an open position and a closed position, means urging said doors toward one of said positions, a cam about at least a side of said axis, cam followers operatively connected to said doors and positioned to contact said cam to move said doors to said other position, and means to seal said packages in said chambers while said ends are closed.

References Cited in the file of this patent UNITED STATES PATENTS 

